Lens-grinding machine



Oct. 12 1926.

L. W. BUGBEE LENS GRINDING MACHINE Filed Sept 19,

1924 3 Sheets-Sheet 1 l ,l l l I INVENTORl I ZUf/fl/Y 1445068 2ATTORNEY-5.

Oct. 12 ,1926. 1, 02,522

L. W. BUGBEE I LENS GRINDING MACHINE Filed Sept. 19, 1924 6 Sheets-Sheet2 ITHEHIIHHIH 17 i ///%/V// i i lujiclliii 11212 5514 L\ Plq. 43

A TTORNEYS.

Oct. 12 1926.

L. w. BUGBEE LENS GRINDING MACHINE Filed Sept. 19, 1924 3 Sheets-Sheet 5F1 .ll] 8/ I 45 44 s I 15 u 73 l I' I I i 7) 1 l I x f I INVENTOR.

lUC/fl Y M. 306865.

BY I

A TTORNEYJ.

Patented Oct. 12, 1926.

UNIT ED 8 TA T ES PATENT OFFICE.

T fro G urmet; uremia eomemmiiy OF NEWYORK; NJ'YL! .A can:

PORATION OF DELAWARE:

Lms eniziniim mcmim Appiic'e'tiqn filedseptiiibeiqa isz ir Serial No.738,642."

This invention is a 1nachinefor grinding;

torie surfaces' -on lenses; "on the same generalprinciple as shown-inapplieants former 'ap'e IT plieatioii Serial New 653367; filed July 323, 5 192mm a machine "for generating torie'sun" faces; It grinds" one'lens' at'a time an'd is particularl-y adapted for pn-istni otion F WOIkand for grinding-"odd types'fof toricdens'es. Its chief virtue is thatiii-grinds *a theoret- 'ioally true *torus.

The machine herein shown and described contains several improvementsover the machine shown in ndy fdrmer ap lication;

One feature bf thisinveifition consists inm'ountingt-the grinder, "whichhas a periphen :11 surface coneaiie transversely; on a table andniouiltingthelens hdldiiig-nieans-on a carriage jsli'da ole' onsaidtable towards and hone the grinderfiancl said lens holding means beinginountedonsaidcarriage so as to *be capable of oscillating" intheplane'of the grinderfbut have noother movement The F adj iistihe-nt oft'he le'n's heldi'ng ineans enables'it's' fulci-uin to be varied todetermine the "radius of 3 oscillation 1 'thereof, whereby the cum-tine*of' the lens -in" one priiicipa l Other features of the l impiroVementcon-f. sist in secL1ring'.the leris block or holderdn a tubular spindleflI iCl' rovidinga bo'lt ex ten ding therethroiiigh for securing thelens holder-to the spindle also in" said spiri'dle" being longitudinallyadj us'tahle' in a housing tulei'u'ined on said earriageyand means-forclamping said spindle" in adjusted position to. prevent any movementthereof inde'p'lehden'tly of said housing; alsoin *providing a housingin whichsaid lens holdiiig spindle is 'mounted, said housing havingmeans for clamping the spindle and alsohai inglafi eralbeariiigs in thecarriage; and means for looking the carliage "ill adjusted position 1 sothat the fulcrum ofszi id housing can be adjiisted to determine thecenter of oscillation oi" the lens holding ineans; also me'ai'is onthecarriage for loelzing the housifi'g and len's holdingineahs When thelaitte'i extends di ainetrieallytf the grinder-f All theselen's holding"means are rigidly secured in place a aiiy movement except oscillationof thelens' lidldei' in the k-meet thegrinder so 'that' as the machineisoperated; the grinder will determine the *ciiivature in i oneineridiaiiand the radius (if oscillation of the lens holding 11183118will determine the curva- -5 t'ure intheother principatmeridian'. AlsoWith-the -foregoing there is lneansfor; mountin g the grinder so that itis adj 'ustable trans; versely Z of the lens holder for centering theSfl.1iie "'Wlth' re'lerenee to' the/lens holding; meatns.=

Other features 4 of the invention consist' in means foradjustingithepartsofthe ;grinding i1iaehine for accurate operation consist-fing of agaugebai' wlthinea ns forsl idably mounting (:the same in connection iwith the housing for the lens holding means *for' convenient adjust-ment-of the carria ge and lensholdingnieans--"to"obtain a proper Vradius of oscillation of the lens holding 7 IIIBAIISi" Said-gaugebar-isgraduated and has a head that serves "as ;a substitute for thegrindeI-"in making sucl1}adjust1n'ent.- Also a 'gauge'rod islongitudinallyadjustable in the lens holding spindlefor cooperation-With said gauge bar, said gauges determining the "longitudinal movementand adjust-?- ment of the spindle andthe gauge rod being used in thefinal-adjustnient-in connection With the'grinder. The-objeetsofthesead-- 3 jdstmentsof the lens holder are' to; determine t-l1e' 'radiusvofoscillation and also the proper mounting of the ilen's holder- Withoutinjuryto or interference With'the grinder, and in 'l0ing=this,the-lensholdingein'eans' B5 isoscillated or turned-upi away-from the grinderwhile effectingwsaid adjustments;- Thesenieans 'for adjustments make themachine practical-{accurate and coinplete and enable it to f besatisfactorily' used.

The full nature of theinvention-Will be understood from 1 theaccompanying -Cl1:8LW- ings"and the following description J and claims:A

In thedrawings,Figure 1 isa pla'n View of'a part-of said machine forgenerating toric surfaces on lenses'with 'some ofthe adjusting meansimposition and-parts broken away. Fig.l2-is a central Vertical sectionon the-lineQ 2 of Fig; 1-, shmv'ingparts in sideelevationandpartsbrokenaway. Fig. 3 is a lan""vieii of 'a'graduatedgaugebar for' use in the preliminai 'y'adjustment of the carriage of the lensholding meehanism in predetermining' the' center i of oscillation of 1the lens "holdihg means so as tocause the lens "to have 'the' desiredcuirvatnre '--in*tl;1 e equatorial 0110116 principal'nieridianz' Fig.

4 is a central vertical section through the lens holding means with saidgraduated gauge bar shown in side elevation, the parts being inunadjusted position. Fig. 5 is the same showing the parts in adjustedposition to determine the desired grinding radius. Fig. 6 is a sectionthrough the lens holding means and part of the grinding wheel showingsaid lens holding means in position of final adjusting for the grindingradius, said graduated bar being removed. Fig. 7 is a section throughthe lens and lens holding means with the graduated bar shown in sideelevation for determining the adjustment of the spindle carrying lensblock and lens. Fig. 8 is a central vertical section through the lensholding means and a part of the lens grinder, the remainder of thegrinder being shown in elevation and different positions of theoscillation of the lens holding means being indicated by dotted lines.Fig. 9 is a plan view of the grinder and the lens holding means withmeans for centering them with relation to each other. Fig. 10 is anelevation of the left-hand end of Fig. 4:.

In the machine herein shown "for the purpose of illustrating the generalnature of this invention, there is a table or base plate 10 on which thelens grinder and lens holding means are mounted. The lens grinder 11, asherein shown, is a rotary lens grinding wheel with its grindingperiphery transversely curved so as to be concave and to determine themeridional curvature of the surface of the lens blank ground. Thegrinding wheel is adjustable on a shaft 12 mounted and carried in ahousing 18 and driven by a sprocket wheel 1 1 from some suitable sourceof power. The grinding wheel is longitudinally adjustable on said shaftby being splined thereon and is held in adjusted position thereon by thelock nuts 15 on the threaded portion of the shaft and the lock nut 16on. the other side of the grinding wheel. The particular manner ofmounting said grinding wheel so as to make it laterally adjustable andit is immaterial as to which of the two members, the grinding wheel andthe lens holding means, is laterally adjustable. All that is necessaryis to center them with reference to each other, as hereafter explained,in order for the lens surfaces to be properly generated.

The lens holding mechanism, broadly stated, includes a carriage 20 andall means carried thereby. Said carriage is movable and adjustabletowards and away from the grinder and the particular manner of mountingsaid carriage so as to have such movements on the table 10 constitutesno essential part of this invention. The means for such purpose hereinshown includes an upwardly extending track 21 integral or other wisesecured an the table 10. The carriage 20 has an A-shaped groove 22 whichrides on said track 21 and guides the carriage in its movements. Saidcarriage is held in place by two holding bars 23 and 24 that are securedto the table 10 by screws 25. These provide a guideway for the carriageand it is moved by a screw 26 which has on its outer end a hand wheel 27and the screw is mounted in a bearing 28 on the table 10 and is heldfrom longitudinal movement by collars 29 on said screw and the screwoperates in a threaded block 30 secured to the underside of the carriage20, as seen in Fig. 2. W hen the hand wheel 27 is moved in onedirection,said carriage is fed towards the grinding wheel and when reversed, it ismoved away from the grinding wheel. W hen said carriage is adjusted, itis locked in adjusted position by a set screw 81 extending through oneof the guide bars 23, as shown particularly in Fig. 2.

The lens blank 35, as seen in Figs. 7 and 8 is mounted on a lens block36 which has a reduced. portion 136 that extends into a tubular seat 37in the end of a spindle 88 and is held therein by a screw rod 39 whichextends through a central aperture 4:0 in said spindle, and the screwrod 89 has a head 41 at its right hand end and it can be locked inposition by a set nut as or a set screw T3 which extends through thespindle, as shown at the left hand. of Fig. '7.

The lens holding spindle is longitudinally adjustable in a housing 43which is central- 1y split at 1-1 onthe upper side, as shown in Fig. 1,whereby the housing can be clamped by a bolt 15 so as to hold thespindle from movement after its adjustment therein. The housing isoscillatably mounted by means of trunnions 4-6 and 1? in transversealignment with each. other, and trunnion pins 48, as shown, which aremounted in bearings 49 and 50 on the upper ends of the arms 51 extendingupwardly from the carriage, as seen in Figs. 1 and 2. The bearing pins18 are threaded for adjustment and locked by a collar 52. The axis ofsaid bearing members is the center 01"- oscillation of the lens holdingmeans and fixes the grinding radius or radius of oscillation of the lensholding means and that determines the equatorial curvature of thesurface ground on the lens blank.

The spindle 38 is longitudinally adjustable in its housing 13 by meansof a screw rod which is mounted in a collar 61 on the right hand end ofthe spindle and held from movement therein by the collars 62 and isturned by a knurled head The screw rod 60 extends through the threadedaperture in the housing. as seen in Fig. 1. When the spindle isadjusted, it is held in adjusted position by the tightening of theIflul] 15 of the housing as, as explained heore.

7L rat. a; .i; 1,602,522

To prevent the lens holding from, being moved towards thegrinding vvheelstop rod abuts against the housing 43.

The foregoing description explains the construction of the machineforgrind ng lenses. It viskse'en that the lens is not 110 tated while'beingground, as the lensfholder has, no movement except oscillation in theplane o'f the grinder. The operationof the against the grinding face thelens blank, which causes the ground surface of the lens blank to have ameridional curvature, the same as the transverse curvature of thegrinder, and an equatorial curvature c0ncentric w th the center ofoscillatlon of the lens holdingmeansi I 1 v ;The lens holding mechanism1S OSCllliltQd in the machine hereinshown by a handle 67' ina collar 68heldonthe tumbler 47 by a set screw 69, as seen in :Figsfl andalthoughthe invention is not limited to any special means forcausingsuch oscillation During-the adjustment the lens holding means,fi.ncludi1 1g the housing 43, are locked against oscillation with the spindle38in horizontal positionbv a locking bar 167,

- shown in F ig. 1, that isthinged between the two ears 168 to thenon-oscillatory bearing 50, so that the lock "167 can'be turned downinto a recess 169 in the tumbler 46 and thus lock the housingagainstoscillation. The

1y on the shaft until the center of itstrarisverse concave curvature iscut by the axis of the lens holding means or spindleBS'fvvhen the axisofsaid spindle also cuts the axis of the grinding wheel. Duringthis'j'adj'ust c mer t a T-shaped gauge 70 is employed It consists of; ardd-likeshank portion tliat i s insertahle in the central opening of thespindle and turned until the tvvo pointers 71 on the'jhead 72 are inthesameplaneas the axis of the grinding Wheelf Theihead '72 is at rightangles to the shank ofthe carriage andjthe twopins project therefromequidistantr Thegauge is'locked in position by the clamp screw 73. Thenthe vspindle 38 is v Inoved]tovv ards the grinding Wheel by turning thehead 64. n" the utting-feast 60 I moved, longitudinally owards'i "auto ypfointersf 71 i n' lt i-r r fie y brut in g wheel; *as"sho'iivn-inFigf9, Thisfcent'ers the spindle and" grinding vvh'el, iDuring "this; operation the-manning screvf' lh 11as;bee rela'X'edQ"soasfto]permit the" pindle" to j j the am ng? Whee1';f after grindingfivheel and len sj harder-aretemer d,explai ed, materials? is moved aw yire-urine grinding vheel and" '16 oscillated "upward and 'the"c'enteringgaug d i i 70 is removed. machine after its adjustment isillustrated" in; Fig. 6, the grinder beingrotated and the lensho'ldingme'ans being oscillated in avertical; plane, as indicated tomove and hold In orderto' adjust and? erly'ldcateth? airisv 'jorceiiterfof "oscilla on ofjthfe fle'rrs homer, softhat the' grindingjradius'orraditis] of oscillation of tli 'lens'tho'l'djerf i sfsu ch astof predete'rmiii the desired equatcriar u ve-g ture of the lens surfacebeing grOundQ' the' follo ving'meansiand math-(mare elnploved;graduatediscjalef ar-175 'is erriployed, s 1ibg stantiajlly as 's'hov'ihin Fig; 3, with a1 1e"ad76 and; an adjustable" screw!- 7? in jthe en jdoff said head" There is also" a'mi'lliineterjscale': 78 and 'a settingslide ninete n? The au e bar '75; is inserted mm "musing 013 holder 80therefor, as' seen in F igi lfand is clamped in position fand'f adjustedby a sc'rwBl. The' slide'f7 9 isjset on thekatri bar at thedesiredgrindingradius 'as lnt li-I I cated the gr'adufz'rtins thereon,said grinding; radius extending from""the" left-f hand race; of the"setting "slide '79 to the inner end ofthesetscrevvflj inth'e'headm f Sra gaugejas seenfin Fig. 3. Whn it is inount ed" in connectibnf with ueleis herding eans; said gdi'i e "bafr is movedtoj the peertion'ffslioyvii, in? igjt, so"'tha t" tlie settin slide" ialfiutfsfage-inst thefhdusingfand it "is obs rved hat thetliicknes"ofsaid"slideliis the same as the," between the 4 fleft hand Tend iof the;housing 8 0 or 43" and center 821' of the gfradius or radiusofoscillation. 'ljhenfthefsetfscrevyf'slf is tightenedso sto'iholdtlidgaugejbar '75- in such 'positio flhat brings the left-hand I I e-79Iinf1i 1 e vitli thecenter of osmium-611 82; Theiniier'end'of the setscrew 77, therefore, represents the position the "centeir' of transversecurvature of the griridingfiac'e of the rinding Wheel.

' Thenext step'in tliisadjustment; is to inin Fi'gS 4 and f5 havingjinits left-hand end 8Q dlk 84 fQIfIn CT of hard rubber or other 7 desiredmaterial and *rotatably niouhtedin the end gauge rokl"'83: Theiisaidgauge rr' 5d8 3 is: moved up until rsaiid 'di 'sk 84lthe "inner endfofthe screw "7 as seen in'Figjj 5, At" that point'the set screw s' f i iii d w Dl'iring the forego ngf ad 'us'tment the carrlageh'a's notbeemmov'edupfto the-grinding 'xvhe'el beta se tlie mechanism hasnot beenadjusted to indicate hovv up te move it.

leaving only the gauge rod 83 in place, as.

shown in Fig. 6, and then the lens holder is oscillated to bring thespindle 38 and gauge rod 83 into horizontal position. At that time it islocked by turning down the lock 167, as shown in Fig. 1. Then the gaugeis moved up towards the grinding wheel until the disk 84- at the end ofthe gauge rod 83 touches the grinding wheel, as seen in Fig. 6. Thecarriage remains held in its adjusted position by the feed screw 26,whereby it is moved up to the position shown in Fig. 2, and that locatesthe generating center or center of oscillation of the lens holding meansduring the grinding of the lens blank and predetermines the equatorialcurvature of the surface ground thereon.

The next step in the adjustment is mounting a lens blank on the lensholder. To do this, the lens holding means is unlocked and oscillatedfrom the horizontal position shown in Figs. 2 and 6 to the upper dottedline position shown in Fig. 8, and again the graduated gauge bar isreplaced in the machine, as in Fig. 5, and the spindle released from itsclamp and slid backward and the gauge rod 83 remover. and the lens blanksecured on the block 36 and said block inserted in its spindle and heldtherein by the rod 89 and associated parts, as shown in Fig. 7. Then thespindle is moved up to bring the lens blank against the end of the screw77, as seen in Fig. 7, and the housing 43 clamped by tightening the nut45. This insures the spindle against further movement and the lens blankis mounted ready for grinding by oscillating the same vertically, asshown in Fig. 8, across the grinding face of the grinding wheel. This isline grinding of the lens blank, as the grinding wheel and lens blanktoucli only at one transverse line, but thereby the me ridionalcurvature in determined by the transverse curvature of the grinding faceof the wheel and the equatorial curvature by the radius or oscillationof the lens holding means.

For accuracy in the grinding operation, the set slide 79 is readjustedon the gauge bar 75 before it is replaced in association with the lensholder, as shown in Fig. 7, to allow for the thickness of the glass thatis to be ground away from the lens blank. This is determined by theoperator and the millimeter scale on the gauge bar 75.

As seen in Fig. 10, the gauge bar 75 is set to the left hand of thevertical plane through the center of the lens holding spindle 38 and,therefore, the head 76 of said gauge bar is inclined so as to bring thescrew 77 in exact alignment with the center of the spindle It is alsonoted that the lens holding means is prevented from engaging andinjuring the grinding wheel by the stop rod 65, see Fig. 6, which limitsthe movement of the lens holding means towards the grinder.

The invention claimed is 1. In a machine for generating toric s-irfaceson lenses, a table, a rotary griider mounted thereon with its peripherycurved so as to be concave transversely to determine the curvature ofthe lens in one prin cipal meridian, a carriage slidably moun ed on saidtable, means for adjusting it towards and from the grinder, a housingmounted on said carriage so as to oscillate in the plane of the grinder,a spindle longitudinally adjustable in said housing, and a lens holdermounted in said spindle, whereby the radius of oscillation of the lensholder may be adjusted.

2. In a machine for generating toric surfaces on lenses, a table, arotary grinder mounted thereon with its periphery curved so as to beconcave transversely to detcrmine the curvature of the lens in oneprincipal meridian, a carriage slidably mounted on said table, means foradjusting it towards and from the grinder, a housing mounted on saidcarriage so as to oscillate in the plane of the grinder, a spindlelongitudinally adjustable in said housing, a lens holder mounted in saidspindle, whereby the radius of oscillation of the lens holder may beadjusted, and releasable means on said carriage for locking said housingwhen in position for holding the lens holder radially of the grinder.

3. In a machine for generating toric sur faces on lenses, a table, arotary grinder mounted-thereon with its periphery curved so as to beconcave transversely to determine the curvature of the lens in oneprincipal meridian, a carriage slidably mounted on said table, means foradjusting it towards and from the grinder, a housing pivoted on saidcarriage and being split, a spindle longitudinally adjustable in saidhousing, means for clamping said housing for holding the spindle inadjusted position, and a lens holder secured in said spindle, wherebythe radius of oscillation of the lens holder may be adjusted.

4. In a machine for generating toric surfaces on lenses, a table, arotary grinder mounted thereon with its periphery curved so as to beconcave transversely to determine the curvature of the lens in oneprincipal meridian, a carriage slidably mounted on said table, means foradjusting it towards and from the grinder, a housing mounted on saidcarriage so as to oscillate in the plane of the grinder, a tubularspindle longitudinally adjustable and secured in said housing, a lensholder mounted in the end of the said spindle, and a bolt extendingthrough said spindle for securing said lens holder in place, whereby theradius of oscillation of the lens holder may be ad usted. cipalmeridian, and means for holding said p5, In,a machine forgeneratingtorio surparts intheir adjusted positions. i .H i-ii yr w "a Mw 'g"" in, w jaces on lenses, a able, a rotary gr nder 9 111 amach neforgeneratlng toric surrnopntedfthreon, wi h its peripheryj curved faces onwa er -grinder with v so as to be, concaye transversely to, deterts IJQILiJhG IY lZHrYeQ v transversely so asto mineYthecurvature of thelen ione, Prme determme the fcu'rvatu're' of" th'e le'ns 'bla'nk cipalmeridian,a,carriage,slidablyinountedfinlone principal meridian, a"carriagemovonsaid table,meansfor adjusting it towards; towaigdsiandaway'ffroni the grinder, a and. from-the ,grmder, a housingi m ounted j,housmg; mounted on said carriage and oson said earr age so as to'osclllat i'u 'thejc ll'atable" on an'axis'parallel with'the axis planeof Qthe 5 grinder, a tubular spindle; of the grinder, a 7 lens holding"spindle longilongitudinally adjustable in said housing, a jtitdinallyadjustable in said housing,ine ansglans holdermountedin the end ofsaidspinf for clamping the spindle adjusted posi dl a bo t-exte d n thms sa d; pin e idn. nfth oh' s; gauge for determining for securing saidfliolder in place, and a jthei p ree er the'c arriagelso-that the axisa:

Screw extending through the spindle into of osc'rllation housing andlens holdengagement with said bolt for preventing ng' spmdle wlllbetheproper distance from itt ,t faces. lense amounted th rei with i s ,r p ecurved rmnttn a hereby l arad o -w lfl ii fi il e il Y le W196altiomqtthedens holder may be, adjusted., 'g1f91 ind to the desred",ourvature, and means 6.- n; a, machine for gable, Ma rotary grinderposition.

10. In mach ne for generating ,toriosura talb i some"? tra vers o te m eflfa s' bnll 's. blank wary g w the ou wature of the,"le ns in oneprincipal its peripheryj curved transverselwso a to meridian, a ,carriageg slidably mounted on determine the'curvature oft-he Inns blank lsaidtable, means for adjusting it towards in, onelprincipal meridian,acaririage mov-' the; sen means i o' g; a let ward ndawa fw i h sr j isaidjloarr age in, ad usted position, a 'ho'us', h llfilng 'wlth, twojlaterally extending por- 'ingmonntedpn saidparriage so asto oscilf tion's pivotallyjinounted on said'car'riage and late in;,the ,pl,ane thegrinder, a spindle{ with an open ng throulgh the central part of alonsindinal y djust-ab in a said u the lious na ale l dingspindle longituanda lens holder mounted in said Tspiiidlemdinally 'n iovable'jin' saidopening infth e hous whereby th iradiu l f s t n f t l e o l y baadjn fi1 mg and t owardsia-nd thegrinder, 1 means for, 'ola'mping" the spindlein a'dju'sted 7 ,3 a v maehine for; generating toric sur-f posi'tion inthe housing, a gauge Tori-deterfaces on lens blanks, a r-otarygrinder'with miningthep'ositionof the axisof said h'ousitsperipherycuryed' transversely so as to,"in nnrear to the grinderiin order todetermine the curvature of the lens blank predete gmine the curvatu'rein the other in one principal meridian, a lens holder 0 p iifllpalfhleiiidiangin theflen s blankflbeing i l A Hi W1 1,5 a." Jllatablefor, mov ng; the lens blank to and ground, and means 9 0 1 5;hecarriage l'ffil;

holding it against the periphery of the in djusted position. grinder, acarriage movable towards and 11. In a machine for generating toricsuraway from the grinder, means carried by the faces on lens blanks, arotary grinder with generati g .toric sur-j for holdingthe carriage.'such'adjus'ted carriage for providing a fulcrum for said its peripherycurved transversely so as to delens holder, means for determining thelooatermine the curvature of the lens blank in tion of the center ofoscillation of the lens One principal meridian, a lens holdingspinholder to predetermine the curvature of the dle, .a housing in whichsaid spindle is lens blank in the other principal meridian, mounted soas to be longitudinally adjustand means for holding the carriage inadable towards and away from said grinder, justed position. means formounting the housing so it will 8. In a machine for generating toriosurbe osoillatable and the axis of oscillation he faces on lens blanks,a rotary grinder with adjusted towards and away from the grinditsperiphery curved transversely so as to er, means for determining theposition of determine the curvature of the lens blank in the axis ofsaid housing with reference to one principal meridian, a lens holdingspinthe grinder so as to predetermine the curvadle, a housing in whichsaid spindle is ture'of the lens blank in the other principal mounted soas to be longitudinally adjustmeridian, means for holding said parts inable towards and away from said grinder, their adjusted positions, andmeans for limmeans for mounting the housing so it will iting themovement of the spindle towards be oscillatable and the axis ofoscillation the grinder and with reference to the h0usbe adjustedtowards and away from the ing. grinder, means for determining theposition '12. In a machine for generating toric surof the axis of saidhousing with reference faces on lens blanks, a rotary grinder with tothe grinder so as to redetermine the its periphery curved transversel soas to curvature of the lens blank 1n the other prin determine thecurvature of the lens blank in one principal meridian, a carriagemovable towards and away from the grinder, a housing with two laterallyextending portions pivotally mounted on said carriage and with anopening through the central part of the housing, a lens holding spindlelongitudinally movable in said opening in the housing and towards andaway from the grinder, means for clamping the spindle in adjustedposition in the housing, a gauge for determining the position of theaxis of said housing with reference to the grinder in order topredetermine the curvature in the other principal meridian in the lensblank being ground, means for holding the carriage in adjusted position,a collar on the rear end of the spindle, and an adjustable rod mountedtherein in position to engage the housing and limit the movement of thespindle towards the grinder.

13. In a machine for generating toric surfaces on lens blanks, a rotarygrinder with its periphery curved transversely so as to determine thecurvature of the lens blank in one principal meridian, a lens holdingspindle, a housing in which said spindle is mounted so as to belongitudinally adjustable towards and awa from said grinder, means formounting tie housing so it will be oscillatable and the axis ofoscillation be adjusted towards and away from the grinder, a removablegauge rod adjustable in and longitudinally of said spindle in positionto engage the grinder when the center of oscillation is at such distancefrom the grinder as to cause the lens blank to have the desiredcurvature in the other principal meridian, and means for holding saidparts in their adjusted positions.

14. Means for adjusting a lens holding mechanism in relation to agrinder, including the combination with a grinder, and oscillatablemeans for holding the lens blank in proper position for treatment withthe grinder, of a gauge bar slidably mounted on said lens holder havinga head adapted to be held in front of the lens holder for indicating thedesired radius of oscillation of the lens holder between the fulcrumthereof and the head of said gauge bar, a gauge rod centrally mounted inassociation with said lens holding means and projecting beyond the sameto engage the arm of said gauge bar, and means for securing said gaugebar and gauge rod in their adjusted positions.

15. Means for adjusting a lens holding mechanism in relation to agrinder, including the combination with a grinder, and oscillatablemeans for holding the lens blank in proper position for treatment bysaid grinder, of a graduated gauge bar slidably mounted in said lensholding means having a head adapted to be held in front of the lensholder, a setting slide on said gauge bar to enable the gauge bar to beset in proper position for indicating the desired radius of oscillationof the lens holder between the fulcrum thereof and the head on saidgauge bar, a gauge rod centrally mounted in association with said lensholding means and projecting beyond the same to engage the arm of saidgauge bar, and means for securing said gauge bar and gauge rod in theiradjusted positions.

In witness whereof, I have hereunto aiiixed my signature.

LUCIAN W. BUGBEE.

